Current implantable pulse generators (e.g., pacemakers, defibrillators or implantable cardioverter defibrillators (“ICD”)) employ header/feedthru designs that are difficult to assemble. For example, as shown in FIG. 1, which is an isometric view of a feedthru/header assembly 5 of a prior art ICD 10, eight feedthru wires 15 extend through the ICD housing 17 via ceramic insulators 20 to couple to connector blocks 25. Four wires 15 pass through each small circular insulator 20. During assembly, each wire 15 must be inserted through its respective insulator 20 and then formed such that it can reach its respective connector block 25 without being too close to adjacent wires 15, adjacent blocks 25 or the ICD housing 17. Each wire 15 is then welded to its respective connector block 25.
As can be understood from FIG. 1, should spacing be insufficient between adjacent wires 15, between a wire 15 and an adjacent block 25, or between a wire 15 and the ICD housing 17, a short can occur and lead to catastrophic failure of the ICD 10. Thus, the assembly difficulty and shorting potential associated with current ICD header/feedthru assembly designs results in manufacturing costs and failure rates that are higher than desired. Manufacturing costs are further increased by the use of platinum for the wires 15.
Once each wire 15 is welded to its respective block 25, a header 30, which is shown in phantom line, is cast about the wires 15 and blocks 25. However, as can be understood from FIG. 1, the wires 15 and blocks 25 combine to form complex and cumbersome geometries that can lead to air voids within the formed header 30. Such voids require drilling and filling in order to reduce the likelihood of a short occurring across the void. Such rework unnecessarily increases manufacturing costs. Additionally, due to the large amount of material that must be cast to encompass the wires 15 and blocks 25 and form the header 30, curing times for the cast material can be substantial, further increasing manufacturing costs.
There is a need in the art for a feedthru/header assembly with increased reliability and decreased manufacturing costs. There is also a need in the art for a method of manufacturing such a feedthru/header assembly.